Step inside this serene upstate New York retreat perched on boulders

Around 20,000 years ago, the state of New York was blanketed in an ice sheet that, at its thickest, measured two miles deep. As it melted, the glacier revealed a wild, new terrain, defined by landforms such as the Hudson River Valley, Long Island and Niagara Falls. But architect Vincent Appel, founder of Brooklyn-based studio Of Possible, was taken by humbler Ice Age relics: rocks – specifically, the fieldstone and glacially deposited boulders that dotted the site of his most recent project in upstate New York.

Tour a upstate New York retreat that embraces its site

Appel had been tapped by a Manhattan couple to design a small guesthouse, on their property in rural Columbia County, that could serve as a studio and host visiting family. The couple had built a weekend residence on the site about a decade ago – a glass-and-steel house that cantilevered boldly over a pond – but the experience had been a challenging one. The brief to Of Possible was to create a guesthouse that could be regenerative and healing. Appel says, ‘That begged the question, could it also be an alter ego to the original?'

During a walkthrough of the site, the architect discovered a historic stone wall, likely built by farmers in the late 18th century from the rocky glacial soil. ‘We thought, if the original house floats over the pond, maybe the guesthouse could float over that wall,' says Appel. To do that, the architect devised a novel idea in the spirit of a fieldstone wall to perch the building atop large Ice Age-era boulders known in geology speak as glacial erratics.

The architect and his team further clarified their design, using the existing house as an aesthetic counterpoint. Unlike that building, the guesthouse would have a small, efficient footprint of just under 1,000 sq ft. Instead of steel and glass, it would be made from timber and rock, materials that deferred to the site. The interiors, meanwhile, were to remain minimal and warm, not unlike a hotel that the couple enjoyed visiting in Norway. ‘This was going to be a small house, but we still wanted it to feel capacious, warm and beautiful,' they say.

To build it, the team left no stone unturned – literally – in search of boulders that would serve as the structure's ‘legs' while also having the ‘right stance and right presence'. ‘We looked at every glacial erratic within a 35-mile radius,' says Appel, who eventually found two perfectly sized boulders formed from a combination of granite and gneiss on the acreage. Two heftier, 12ft-tall stones, meanwhile, were selected from a nearby quarry. ‘It's like Noguchi trying to find the right surface to carve,' he jokes. Once the stones were selected, and their tops and bottoms were trimmed off, they were craned onto the site, lowered onto concrete footings and secured with stainless steel pins. The minimal gabled guesthouse was then framed out and built on top.

Unlike most houses, you enter this one from beneath, scaling a discreet stainless steel staircase to the front door (look closely and you'll spy the same hardware used at Le Corbusier's La Tourette monastery, near Lyon, France). ‘It is metaphorically an embrace,' Appel explains. ‘When you ascend, the building is hugging and wrapping around you.'

Like the exterior, which is covered in an open rainscreen made of local tamarack (a type of larch), the interiors are entirely clad in timber, lending it a comforting, Scandinavian-inspired aesthetic. In lieu of operable windows, the team opted to install large expanses of glass into the framing itself, a move that would help with energy performance and keep the overall project budget in check.

There are two snug bedrooms, each equipped with custom-built beds and storage; a bathroom; and a spacious open-plan living room and kitchen, which is anchored by a custom-designed island carved from a single block of serpentine marble (the same stone that Mies van der Rohe used in his design for the Seagram Building in New York). The furniture is equally architectural and considered – pieces include some cork stools from Herzog & de Meuron's 2012 Serpentine Gallery Pavilion; vintage pieces by Finn Juhl and Hans Wegner; and a sculptural white coffee table by young New York designer Mike Ruiz-Serra.

Appel has called the guesthouse The Findling, German for both ‘orphan' and ‘glacial erratic'. But one of the clients has another name for it – Heaven. ‘There is a kind of sealed-off character,' he explains, recalling an afternoon of quiet study spent in the new retreat. ‘It's so tight, so perfectly boxed, that you feel you're inside a kind of impenetrable, safe rectangle where nothing bad can happen.'

ofpossible.com